Tick Rate for a large server?

I currently run a server that gets >100 players and at a target tickrate of 33. However, when the server is more full, the server lags down to a tickrate around 10-15 (as seen in net_graph 4). This way, when the server is more empty the tickrate can be higher.

Is there any downside to doing it like this? I could set the tickrate to 11 like some other big servers do and it wouldn’t vary, but is there any reason to lower it it?

I’d suggest rolling with tickrate 16 and just generally making sure your gamemode and addons are optimized properly.

Right, my serverside LUA is about as optimized as possible. What I meant was, what is the reasoning to set your tickrate lower, rather than leaving it at 33 or higher and just letting the server run as fast as it can?

The rationale, as far as I understand, is that with a lower tickrate, the server doesn’t try to do as much constantly. The less often the server has to create snapshots and send them to the client, as well as run hooks like Tick and Think, the less CPU power and bandwidth will be used.

The tradeoff, of course, is less precision. See here for further reading.

Plus, not that it really matters for some gamemodes, timing inaccuracy. E.g. wire expression 2s running at half / slower speed, etc.

I’d always rather have my server at the set tickrate rather than have it struggling to keep up to a number that’s too high.